This application claims foreign priority from JP 10-005954, filed Aug. 6, 1998.
1. Field of the Invention
The present invention relates to an automatic time setting apparatus for an electronic device which receives transmission radio wave in which time data is inserted, extracts the time data from the received transmission radio wave and performs time setting operation of a clock means within the electronic device in accordance with the extracted time data, and also to an automatic time setting method.
2. Description of the Related Art
Recently, many electronic devices contain therein clock functions. This clock function serves to perform, for example, the setting operation of the current time in accordance with the initial setting menu which is displayed when a user who bought the electronic device inserts a plug thereof into a socket and turns on a power switch.
For example, in a television receiver (TV), a video cassette recorder (VCR) containing a tuner or the like, the automatic presetting of the receiving channels is performed and then the time setting of the clock function is performed succeeding to the automatic presetting. In Europe, there is a broadcasting station which transmits a television signal in which time data is inserted at synchronizing signal portions of vertical blanking intervals thereof, and the time data contained in such a television signal is extracted and the time setting of the clock function within the TV or the like is performed in accordance with the extracted time data.
That is, after the automatic presetting is performed thereby to automatically set the receiving channels, a selection menu for selecting whether the time setting (automatic clock setting) operation is to be performed automatically or manually is displayed on a television screen or a display panel of the VCR or the like. When a user selects the automatic time setting operation, then another selection menu is displayed for selecting whether a channel from which the time data is obtained is to be retrieved automatically or manually. When the user selects the automatic channel retrieval, hereinafter, the broadcasting station transmitting the television signal in which the time data is inserted is retrieved from the broadcasting stations set at the respective channels, then the time data contained in the television signal transmitted from the broadcasting station thus retrieved is extracted, and then the time setting operation of the clock function is performed.
In this manner, conventionally there have been proposed various types of automatic time setting apparatuses in each of which the automatic or manual operation can be selected from the selection menus displayed on the television screen or the display panel, and the time setting operation can be performed automatically by selecting the automatic operation. For example, a clock with radio correction function is disclosed in Japanese Patent Unexamined Publication No. Hei. 8-201546 as an automatic time setting apparatus for performing the time setting (automatic correction) of the clock function by the user""s button operation.
In this manner, conventionally there have been proposed various types of automatic time setting apparatuses in each of which the time setting operation is performed automatically. However, in each of these automatic time setting apparatuses, a user is required to select whether the time setting operation is to be performed automatically or manually and to select whether the retrieval of the channel for obtaining the time data therefrom is to be performed automatically or manually. That is, after the user selects these menus, the time setting operation of the clock function is performed automatically.
Thus, for example, if the user suspends the operation, for any reason on the way of selecting the menu, for selecting whether the time setting operation is to be performed automatically or manually, there arises a problem that the time setting operation of the clock function is remained not being completed.
Incidentally, Japanese Patent Unexamined Publication No. Hei. 5-249256 discloses such a system that, when it is determined that the clock of a receiver such as a VCR is in an initial state, the clock of the receiver is automatically set on the basis of the time data contained in the television signal transmitted from a broadcast station.
Further, Japanese Patent Unexamined Publication No. Hei. 5-176035 discloses a button telephone device wherein the time signal service within the public line is automatically received at every constant time period, then the time data is discriminated from the audio signal contained in the received time signal, and the time of an internal clock is corrected on the basis of the discriminated time data.
The present invention has been made so as to obviate such conventional problems and an object of the present invention is to provide an automatic time setting apparatus for an electronic device which can perform the time setting operation automatically after the lapse of a constant time period even if a user does not perform any operation for the time setting, and to provide an automatic time setting method.
In order to achieve the above object, according to a first aspect of the invention, there is provided an automatic time setting apparatus for an electronic device which receives transmission radio wave in which time data is inserted, extracts the time data from the received transmission radio wave and performs a time setting operation of clock means within the electronic device in accordance with the extracted time data, the automatic time setting apparatus comprising: measuring means which starts measuring a constant time period in response to first turning-on of a power source; first determining means which determines whether or not a first time setting operation of the clock means has been performed; and time setting control means which executes the time setting operation when the measuring means has measured the constant time period, in a case where the first determining means determines that the first time setting operation has not been performed yet.
According to a second aspect of the invention, there is provided an automatic time setting method for a television receiver or a video cassette recorder containing a tuner which receives a transmission radio wave in which time data is inserted, extracts the time data from the received transmission radio wave and performs a time setting operation of clock means within the television receiver or the video cassette recorder in accordance with the extracted time data, the method comprising the steps of: determining, after a lapse of a predetermined time period after first turning-on of a power source, whether or not the time setting operation of the clock means has been performed; and executing automatically the time setting operation when it is determined that the time setting operation has not been performed yet.
According to a third aspect of the invention, there is provided an automatic time setting method for a television receiver or a video cassette recorder containing a tuner which receives a transmission radio wave in which time data is inserted, extracts the time data from the received transmission radio wave and performs a time setting operation of clock means within the television receiver or the video cassette recorder in accordance with the extracted time data, the method comprising the steps of: determining, after a lapse of a predetermined time period after first turning-on of a power source, whether or not the time setting operation of the clock means has been performed; and determining whether or not a television signal in which the time data is inserted is being received, wherein the automatic time setting operation is executed based on the time data when it is determined that the time setting operation has not been performed yet and that the television signal in which the time data is inserted is being received, and wherein when it is determined that the time setting operation has not been performed yet and that the television signal in which the time data is inserted is not being received, the automatic time setting operation is not executed and the two determining steps are executed again after lapse of a predetermined time period.
According to a fourth aspect of the invention, there is provided an automatic time setting method for a television receiver or a video cassette recorder containing a tuner which receives a transmission radio wave in which time data is inserted, extracts the time data from the received transmission radio wave and performs a time setting operation of clock means within the television receiver or the video cassette recorder in accordance with the extracted time data, the method comprising the steps of: determining, after a lapse of a predetermined time period after first turning-on of a power source, whether or not the time setting operation of the clock means has been performed; and determining whether or not a television signal in which the time data is inserted is being received, wherein the automatic time setting operation is executed based on the time data when it is determined that the time setting operation has not been performed yet and that the television signal in which the time data is inserted is being received, wherein when it is determined that the time setting operation has not been performed yet and that the television signal in which the time data is inserted is not being received, the automatic time setting operation is not executed and the two determining steps are executed again after lapse of a predetermined time period, and wherein the two determining steps are repeatedly executed upon every lapse of the predetermined time period until the automatic time setting operation is executed.